The concentration of tropospheric nitrous oxide (N.sub.2 O) has been increasing globally at an alarming rate, and the environmental consequences of that increase are believed to be potentially serious. For example, increased concentrations of atmospheric N.sub.2 O are known to influence stratospheric ozone depletion and may enhance troposheric warming due to the "greenhouse gas" properties of N.sub.2 O.
Significant sources of atmospheric N.sub.2 O include the combustion of fossil fuels, particularly coal and fuel oil, and the generation of N.sub.2 O as a by-product from industrial waste treatments and pollution abatement processes. In an attempt to address the potential environmental impact of these man-made sources of N.sub.2 O, it has long been desired to develop efficient strategies for reducing or eliminating N.sub.2 O from such effluent gas streams.
It is known that N.sub.2 O decomposes above 1800K in the gas phase into N.sub.2 and O.sub.2. Catalytic decomposition occurs at much lower temperatures, but also results in the production of oxygen and nitrogen. Thus, it can be seen that the presence of oxygen in the emission stream may inhibit the decomposition of N.sub.2 O due to the important role it plays in the kinetics of N.sub.2 O decomposition: ##STR1##
A need therefore exists for a method of reducing N.sub.2 O from exhaust gas streams that may additionally contain rate inhibiting amounts of oxygen. The present invention addresses that need.